Unsaturated carbamate



Patented Apr. 2, 1946' UNSATURATED oARBAMATE Franklin Strain, Barberton,Ohio, assignor to Pittsburgh Plate Glass Company, Pittsburgh, Pa., acorporation of Pennsylvania No Drawing. Application February 7,1944,

- Serial N0. 521,444

8 Claims.

This invention relates to a group of new unsaturated ester-amides havingvaluable applications as are described hereinafter.

The purpose of my invention is to prepare new compounds capable of beingpolymerized through olefinic groups into tough strong resins useful incasting and molding processes.

Long chain type esters having terminal polymerizable groups form verydesirable transparent polymers. However, these resins frequently havelow strength properties which make them unsuitable for many uses.Accordingly, it is a further purpose of my invention top'rovide methodsof preparing new resin compositions having greatly improved fiexural andtensile strengths. s The new group of compounds of my invention may beregarded as the N,N'-substituted bis (unsaturated carbamic acid esters)in which the two amide groups are connected by an organic molecularstructure containing two or more ester linkages. By ester linkages Imean oxygen atoms which are adjacent carbonyl groups.

* Thus, a carbonate will havetwo ester linkages. Y

. tional distillation of the reaction product.

ethylene glycol bis (chloroformate). This com-' pound is preferably madeby heating the ethylene glycol bis (chloroformate) at 300' to 600 C.-

and separating the vinyl chloroformate by frac- The preparation isdescribed and claimed in Serial No. 504,292 filed September 29, 1943, byFrederick E. Kiing, now U. S. Patent No. 2,377,085.

The same unsaturated ester amides mayalso be prepared from otherreactants. For example; diallyl carbonate, or'thecarbonate of otherunsaturated alcohols having an olefinic group adjacent the second carbonatom from the hydroxyl group, may be reacted with an amino alcohol suchas ethanolamine, 3-aminopropyl alcohol, or isopropanolamine to formanintermediate which can be reacted with acid chlorides of dibasic acidsto form the new esters. intermediate may be conducted by mixing thereactants, for example diallyl carbonate and ethanolamine, at roomtemperature. 3 This ester interchange substitutes one amino alcoholgroup More specifically, the .new esters are bis [N- :(c'arbalkenyloxy)aminoalkyl] esters of the real or theoretical dibasic acids which arecharacterized by having -two .acid reacting hydroxyl groups eachattached to. a carbonyl carbon atom. The alkenoxy substituents ofthe'new esters contain less than five carbon atoms and an olefinic groupadjacent the second carbon atom. from the oxygen atom therein. Theaminoalkyl radical also contains less than five carbon atoms.

The dibasic acids of which the new compounds are symmetrical esters arethe carboxylic acids, including phthalic, succinic, adipic and malonicacids, carbonic acid and the theoretical his (car-- for one of theunsaturated radicals of the carbonate to form a N-(carbalkenyloxy)aminoalkyl' alcohol. Generally, slight heating is desirable to initiatethe reaction and then-to maintain a moderate temperature of 30 C. or 40C. while cooling periodically. At the higher temperatures the reactionis completed in a much shorter period of time.

The intermediates thus produced are reacted with acid chlorides ofdibasic acids such as adipyl chloride, succinyl chloride, orthe acidchlorides of other dicarboxylic acids, with diethylene glycol bis(chloroformate) or the bis (chloroformates) of other glycols, or withphosgene (the acid chloride of carbonic acid) to produce the newcompounds.

The reaction between the acid chloride and the intermediate is conductedin liquid phase in the presence of an alkaline reagent such as pyridineor other cyclic tertiary amine or an oxide, hydroxide or carbonate of analkali metal or an alkaline earth metal. The reactants are so com binedthat an excess of a strongly alkaline reagent will not exist in .thepresence of the final product at any time. It is also undesirable forstrong alkali to be present in contact with the intermediate hydroxycompound. Accordingly, the intermediate and the acid chloride may bemixed and the alkaline agent added slowly while the reaction temperatureis maintained at nor- The preparation of the catalysts is preferred.

I slowly adding separate streams of alkaline agent having exceptionalhardness and resistance to abrasion and yet having unusual toughnessandfiexural strength. v

The new ester amides are-capable of being polymerized when subjected toheat or ultraviolet light especially in the presence of polymerizationcatalysts such as organic peroxides and organic percarbonates. Whenpolymerized, the liquid monomers gradually become viscous and finallyset to colorless transparent gels which.

are rigid and somewhat tough. If the initial polymerization has beenconducted at a moderate The reaction vessel is advantageously 2,397,031t r r of 110 0. The kind of catalyst should be selected in accordancewith the activity of. the monomer. Very active vinyl derivatives requirelow temperature catalysts since at high temperatures the polymerizationmay be too rapid. Conversely,

relatively less active monomers such as crotyl or cinnamyl esters mustbe heated to relatively high temperatures and require a catalyst whichwill be stable until the higher temperature zones are reached.

In the usual polymerization procedure it has been found desirable toinitiate the reaction at relatively low temperatures. After thepolymerization has begun it is possible to increase the temperature withless danger of heat fracture and discoloration. Accordingly, thequickest satisfactory reaction is obtained by raising the temperature inthe presence of an oxygen yielding catalyst it is possible to obtainanintermediate polymer which contains some unconsumed catalyst. Suchcompositions are capable of further polymerization to form hard clearsolids. When the initial catalytic polymerization is induced at highertemperatures the rate of decomposition of catalyst may exceed the rate,of polymerization and a softer polymer may be formed. Such inefl'icientutilization of' catalyst is undesirable. For each combination ofester-amide and catalyst there is an optimium quantity of catalyst andtemperature of polymerization which may be determined experimentally bybalancing the respective economies of degree of polymerization and costof catalyst against the'time required for polymerization. There is afurther practical limitation on the temperature as rapidly as possiblewithout fracturing or discoloring the product. Such gradually increasingtemperature schedules are more efiicient in the utilization. of peroxycatalysts sincethey promote a more nearly uniform reaction ratethroughout the entire polymerization.

The temperature schedules mayrbe devised by trial and error methods, orthey may be 'determined experimentally by analyzing for peroxy compoundduring the progress of the reaction and regulating the temperature sothat the peroxy compound is consumed at a uniform rate. The followingtime-temperature schedule is typical for the polymerization of bis [N-(carballyloxy)- rate of polymerization. The polymerization reactionbeing exothermic, the rate of reaction must be vslow enough to permitthe dissipation of the heat of reaction. Otherwise, the rise intemperature will increase the rate of polymerization, thereby generatingprogressively increasing" quantities of heat until the uniformity of theHigh polymerization temperatures may also cause dis- Accordingly, lowerpolymer is destroyed by heat fractures.

coloration in the polymer.

temperatures are preferred.

Polymerization takes place in the absence of catalysts, but highertemperatures are required.

Due to the difliculty of maintaining uniform polymerization conditionsand ,due to the discoloration and fracturing induced at higher tempera-;tures, polymerization in the presence of peroxy The quantity and kindof peroxy catalyst to be used should be determined by the nature of themonomer to be reacted. Very active mono- .mers such as the vinyl estersneed only small quantities such as from 0.01 percent to 0.5 percent byweight of the'monomer, while moderately 1 active monomers such as theallyl derivatives may require up to 5.0 percent. It has been found thatdifferent types of peroxy catalysts are eflective at differenttemperatures; for example, the

' percarbonates will catalyze the reaction at 30 to 60 C., acylperoxides are effective at an intermediate range (65? to 95 0.), whilethe ketone peroxides are effective at temperatures in excess aminoethyl]carbonate using benzoyl peroxide as the catalyst:

Temperature Time Home The new esters are useful in many applicationssuchas in coating compositions, in laminated fabrics or in impregnationof cloth or random fiber compositions or as adhesives. They areespecially useful because of the very small loss of volume or shrinkagewhich occurs during polymerization. For this reason they are very usefulin the preparation of cast shapes especially where transparent,translucent or light colored products are required. Generally anirregular shape normally utilizing glass may be advantageouslyconstructed with the new resins because of the much greater toughnessand high flexural strength obtained without much sacrifice in abrasiveresistance.

The new materials may be copolymerized with other thermosetting resinsor with the thermoplastic synthetics such as, vinyl acetate, styrene,

methyl methacrylatavinyl chloride, vinylidene chloride or othermaterials capable of ethylenic polymerization.

Further details of the preparation and use of the new materials are setforth in the following examples:

Example I A mixture of 183 g. of ethanolamine. and 426 g. of diallylcarbonate was permitted to stand at room temperature for 20 hours.During that period the temperature reached a maximum of 44 C. at the endof the first hour. The mixture was heated at 4 mm. pressure at 50 C. toremove the allyl alcohol and excess diallyl carbonate. The residue wasdistilled and the fraction boiling at 127-130 C. (2 mm.) was separated.It was identified as N-(carballyloxy) amino ethyl alcohol.

A mixture of 319 g. (2.2 moles, excess) of this compound, and 174 g.pyridine was cooled to -10 C. by ,submerging the reaction flask in asalt-ice bath. Gaseous phosgene was passed therethrough at the rate of0.020 mole per minute for fifty minuteswhile stirring continuously. Thetemperature did not exceed +8 0. during the reaction. When the phosgene-flow was stopped the thick salt slurry was thinned with 50 cc. benzeneand stirred for 30 minutes. Sufficlent water was added to dissolve thesalt, thus forming two liquid phases. The ncnaqueous layer was washedfive times with equal volumes or dilute hydrochloric acid, three timeswith 2% NaOH and three times with water. The mixture was heated at 25mm. to remove the benzene and at 4 mm. for 45 minutes. A light yellowliquid (n =1.l'780) which solidified upon standing (M. F. 42 C.) wasidentified as his [N=-(carballyloxy) aminoethyl] carbonate:

A. mixture of 3428 g. of N-(carballyloxy) aminoethyl alcohol (seeExample I above) and 190 g. of pyridine was prepared in a 2000 ml.reaction flask provided with a mechanical stirring device, a thermometerwell and a dropping funnel. The mixture was cooled to 0 C. and 187 g. ofethylene glycol dichloroformate was introduced through the droppingtunnel at a rate which permitted the maintenance of a reaction.temperature no higher than 5 C. The product was purified by topping at 5mm. pressure. The ester-amide was ethylene his [N-(carballyloxy)aminoethyl carbonate]; a colorless viscous fluid having anindex ofrefraction (n ==1.47'78) a density of 1.2457 (20 C.) and the followingmolecular structure:

hours. A. clear hard and tough casting was obtained.

Example HI 1 A mixture 01 145 a. of N=(carballyioxy) ms:

ethyl alcohol (see Example I above), 100 g. of pyridine and 100 cc. ofbenzene was placed in a 500 cc. reaction flask fitted with a droppingtunnel, a mechanical stirrer and a thermometer.

While the temperature was maintained below.

+5 C. by means of an ice bath, 102 g. of phthalyl chloride were addedgradually over a one hour period. The reaction mixture was stirred fortwo hours while it was permitted to warm to room temperature. The crudeester-amide was washed three times with 200 cc. portions of dilutehydrochloric acid (5 percent), two times with 4 percent NaOH and finallytwice with water. The benzene was evaporated by heating at 100 C. (4mm.) for one hour. The product, bis [N-(carballyloxy) aminoethyl]phthalate was a yellowish colored viscous liquid having an index ofrefraction of 1.5210 and a specific gravity of 1.227. It had thefollowing structure:

benzoyl peroxide and cast in a sheet mold (6" x t e" x 0.25). A clearalmost colorless sheet of tough hard resin was thereby obtained.

While the invention has been described with reference to certainillustrative embodiments, it will be apparent to those skilled in theart that various modifications thereof may be practiced withoutdeparting from the purview of the invention as defined in the appendedclaims.

What I claim is:

1. As a new compound, a his [N-(carbalkenyloxy)aminoallzyll ester of adibasic acid which acid has two acid reacting OH groups each attached toa carbonyl carbon atom, in which compound the aminoalkyl and alkenoxysubstituents each contains less than five carbon atoms and the olefinicbond in the alkenoxy substituent is adiacent the second carbon atom fromthe oxygen atom therein.

2. As a new compound, bis (N-carballyloxy-' aminoethyl) carbonate. Y 1

3. As a. new compound bis (N-carballyloxyaminoethyl) phthaiate.

4. As a new compound ethylene bis (N-carballyloxyaminoethyl carbonate).

5. A polymer of the compound defined in claim 1 6. A polymer of thecompound defined in claim 7. A polymer oi. the compound defined in claim3.

FRANKIIN STRAIN.

8. A polymer oi the compound defined in claim

